Improvement in piston-packing



To all whom it may concern.-

LUCIUS J. KNOWLES, OF WORCESTER, MASSACHUSETTS.

Letters Patent No. 105,466, dated July 19, 1870.

wm `:M15Rover/mur m PIvsToN-PAcKrNG.

a Thel Schedule xefemsd to in these Letters Patent and making part of the same,

Be it known that I, LUcrUs J. Knowmss, of the city and county of Worcester, and State of liflassachu` setts, haverinvented certain new and useful Improvements in Piston-Pitching; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawing, in which- Figure 1 represents a ring of my improved packing, as prepared for use;

Figure 2 represents a transverse section of the same; and

Figure 3 illustrates the method of construction.

To enable those skilled in the art to which my invention belongs to make and use the same, I will proceed to describe it more in det-ail.

The nature of myinvcntion consists in an improved packing for the pistons of steam-pumpsconstructed substantially as hereinafterdescribed.

My improved packing is composed of heavy canvas 'or duck, and is made as follows:

Several layers or` courses of canvas are placed -together, 'and joined to each other by stitching or sewing them through with strong thread, the seams being formed parallel to each other and at regular intervals, as shown in fig. 3, in which A indicates the canvas and B the seams. The seams B may be parallel with the web of the cloth, as indicated at the lower'part of fig. 3, or diagonal to the web, as indicated at the upper part of said figure.

After the layers-of canvas have been stitched together, the sheet thus composed is formed into strips by cutting it parallel toand midway between the seams B, (see iig. 3,) so that the seam will hold together the diiierent layers of cach strip. These strips are cut to the required length, and formed into rings, by sewing together ytheir ends, as shown at a', iig. 1, when the packing is ready to be applied to the piston, upon which-thc rings are arranged, with the raw edges ot the canvas outward, a sncient number being used to completely fill the groove around the piston. In piston-packing, as heretofore constructed, the diti'erent `layers of canvas have been joined together by means of elastic gum or India rubber, and when packing thus formed isapplied to a practical test, it is found that the rubber becomes incorporated with the vfibers oi' the canvas, and mats them downinto a solid mass,

. thereby greatly increasing the friction of the parts,

and, in a very short time, rendering the packing uniit for use. l j

To overcome these diliculties is the object of my present invention, wherein lthe layers of canvas, being joined by thcseams only, the `bcrs are left free and clean, so that their elasticity is not destroyed; conscquently, as has been .practically tested, the packing fits the cylinder closer and works with much less friction than the ordinarypaeking, while its durability is nnsurpassed.

Having thus described my improved piston-packing,

What I claim therein as new and of myinvention,

and desire to secure by Letters Patent as an improved article of' manufacture, is-

A packing for the pistons of steam-pumps, composed of several layers of canvas orduck, joined together by sewing or stitching, substantially in the manner shown and described,'and for the purposes stated.

LUC-IUS J. KN OWLES. Witnesses: v

Tiros. H; DODGE, GEO. H. MILLER. 

